Radio apparatus



M. w. KENNEY RADIO APPARATUS May 16, 1933.

Filed Dec. 12; 1929 2 Sheets-Sheet l INVENTOR M4; aw A/ ffz/wvsy BYQifia \milw ATTO Y y 16, 1933- M. w. KENNEY 1,909,685

RADI O APPARATUS Filed Dec. 12, 1929 2 Shgets-Sheet 2 INVENTOR MAM! 0/1/A/ KEN/v57 AT.T

Patented May 16, 1933 MAHLOIT W. KENNEY, 0F ELMHURST, ILLINOIS,ASSIGN'OR TO GRIGSBY-GRUNOW COMPANY, 035 CHICAGO, ILLINOIS, ACOEPORATION OF ILLINOIS RADIO APPARATUS Applicationfiled December 12,1929. Serial No. 413,584.

This invention relates to radio chassis and to methods of assemblingthem. The chassis in this case primarily consists of a supporting baseor member upon which the component elements of a set may be supported.in the illustrated form, the set comprises a complete receiver exceptingthe tubes, power supply and speaker. Ubviously, however, any or both ofthese units may be added to the set and supported on the chassis, ifdesired.

In order to efiiciently manufacture and assemble complete radio chassis,particularly in large quantity production, it is essential that theprocess of assembly be reduced to the most elementary details in orderto make use of relatively unskilled labor. It is also desirable that thechassis as a whole be subdivided into small independent units which maybe individually and, if desired, simultaneously assembled. Such aprocedure allows frequent testing of relatively simple units with thespeedy and economical elimination of defective parts, and makes possibleproduction in larger quantities because of the use of such methods.

A further advantage lies in the fact that the rough handling incident toquantity production is limited mainly to compact units which may readilywithstand such handling. Obviously, the servicing of such a chassis issimplified upon the determination of the trouble by the comparativelyready removal of a unit and the substitution of a new one. As is wellknown, radio sets are complicated and their parts rendered relativelyinaccessible because of the close proximity of the various parts and theunavoidable maze of wiring. By subdividing the set into component units,each of which may be assembled or disassembled in a comparatively simplemanner, it is obvious that compactness of apparatus or complexity ofwiring will have but little effect on the servicing of such a set, sincethe defective unit may be removed and replaced as such.

Referring to the drawings,

1 shows a perspective view of a preferred form of complete chassis;

Fig. 2 is a bottom view of the chassis with portion of the bottomcover-plate broken away;

Fig. 3 is a perspective view of a tuning control unit with its housingremoved;

Fig. 4 is a view of the housing for the control units shown in Fig. 3;

Fig. 5 is a view on 55 of Fig. 3;

Fig. 6 is a view of the chassis supporting member with certain of theapparatus removed;

Fig. 7 is a View of two transformers in their housings, which areadapted to be mounted on the chassis member shown in Fig. 6; and

Fig. 8 is a view of a preferred form of radio-frequency unit showing twoof the tube shields and one of the transformer shields removed and avacuum tube plugged into one of the sockets.

The entire chassis preferably consists broadly of a chassis supportingbase 1 having certain apparatus mounted thereon and comprising a unitarysub-assembly. Base 1 comprises a pan having a plate number 2 providedwith openings 3, 4, and 5, as well as smaller apertures for screws andwires and provided with sides 6. In the preferred form mounted withinthe pan and shielded by walls 7 and 8, is an antenna tuning elementgenerally designated as 9 and adapted to be manipulated by a leveragesystem 10 and shaft 11 passing through the sides of base 1. The antennatuning unit may be any one of several well-known constructions.

Secured to the inside of the pan are various pieces of apparatus,excluding audio-frequency transformers, which are employed in detectorand audio-frequency circuits. Part of this apparatus is shown in Fig. 2in dotted lines as mounted on a shelf 13 and connected to a cable 15 forconnection to independent apparatus, such as power units and the like.

Fig. 6 shows a plurality of vacuum tube sockets 16 and 17 mounted on theinside of the pan and registering with apertures in plate 2 so that thevacuum tubes may be plugged in from the outside. A plurality of terminalposts 18 and 19 are provided for connection to apparatus such asspeakers and antenna.

Secured over openings 4 and 5 in plate 2 are a plurality ofaudio-frequency transformers 2O completely enclosed in metallichousings. The housings are mounted on plate 2 by flanges 21 havingapertures registering withv apertures 22 in plate 2, and adapted to bebolted thereon. This assembly cmnprising the audio-frequency and antennatuning unit is substantially complete in itself. A tube shield 25 shownin Fig. 1 is fitted over a flange 26 surrounding sockets 17 before thechassis is finally disposed of. Obviously, the same means may beprovided for sockets 16, if found desirable.

It is evident that this unitary sub-assembly .is sturdy since at allstages of the assembly all the parts are completely protected. Thus, theapparatus mounted within the pan and secured thereto is protected bysides 6 of the pan, while transformers 20 secured to the out side of thepan are completely protected by their metallic housings.

The radio-frequency unit shown in Fig. 8 is assembled on a base member2, which is preferably ti -shaped, having an intermediate portion 30 andside portions 31 and .32. On the inside of this te -shaped member aremounted Various apparatus useful in radiofrequency circuits, such ascondensers 32 and 34 and the like. On the outside portion of 31 aremounted a plurality of radio-frequency transformers 35. Thesetransformers may be of any desired construction and are preferablymounted on circular metallic bases 36 having peripheral flanges 3. W henthese transformers are mounted, metallic shields 38 are fitted overflanges 37 and serve to protect the delicate transformers againstmechanical injury. They also function as electrostatic shields duringthe operation of the transformers.

Along portion 30 of the U-shapcd memher 2 are mounted a plurality ofvacuum tube sockets 40 having metallic flanges ll around them adapted toengage shielding caps 12. A vacuum tube is shown as plugged into one ofthe sockets, although in the course of assembly vacuum tubes and shields42 are not provided. Adjacent each of the sockets 40 are apertures 15,below which may be mounted a plurality of neutralizing condens ers 46.These condensers may be varied by means of a centrally locatedadjustment 4:7 passing through each condenser and in registry with eachof apertures 15. The particular details of construction of thesecondensers are of no consequence. The conden ers shown are useful forintroducing a neutralizing capacity to balance the capacity of thevacuum tubes and, as such, must be adjusted with. the set in operation.This is conveniently done upon the complete assembly of the entire setby the insertion of a proper tool such as a screw-driver or a socket 1wrench through apertures 45 and. into engpgement with the capacityadjusting means It is obvious that the entire wiring for theradio-frequency unit may be disposed on the inside of the U-shapedmember 2. This entire radio-frequency unit is fabricated and assembledas an independent unit. It is clear that during the assembly thereof allparts are protected against mechanical abuse, either because of metallicshields 38 or because of the disposition of such parts on the inside ofsaid mounting member.

Upon the completion of the radio-frequency unit, it is inserted from thebottom of pan 1 and secured to plate 2 over opening 3. Shaft 11 of theantenna tuning apparatus must be out of the way when this is done. Inpractice, this shaft is not inserted into place until after theradio-frequency unit has been in position. The radio-frequency unit issecured by disposing intermediate portion 30 to cover opening 8 in plate2 and is maintained in place by bolts or other suitable fastening meanspassing through a plurality of registering apertures 48.

As clearly shown in Fig. 2, substantially all the radio-frequencyapparatus is within pan 1 to be mechanically and electrically shieldedthereby. Upon the mounting of the radiofrequency unit on plate number 2suitable electrical connections are made between the two units.

It is obvious that during the assembly of the apparatus within pan 1 andbefore the mounting of the radio-frequency unit on pan 1, there isplenty of space available within the pan so that the various pieces ofapparatus may be manipulated and numerous connections made. Thesubsequent mounting of the radio-frequency unit results in an effectiveutilization of free space within the pan without the accompanyinginconvenience of the lack of space during the assembly of each unit.This makes the finished product compact and provides for completemechanical and electrical shielding as well as a covering for theapparatus against dirt.

An independent tuning unit shown in Fig. 3 preferably comprises aplurality of condensers and rheostat 51, assembled upon a base 3. Thecondensers are shown as mounted in a gang on a common shaft 52 carryinga dial *53. A micrometric actuating means comprising a grooved member54c engaging a slotted edge of dial 553 and actuated by a knob 55 ismounted on base 3 in a well-known manner. If desired, small variablecondensers for equalizing the individual condenser units may be mounted,in the conventional manner, upon base 3. The control unit is mountedupon plate 2 by suitable bolts in base 3 engaging threaded bushings 58and is completed by a housing 60 which is fitted over the unit andsecured by bolts passing through apertures 62 and 63 in plate 2. Aplurality of apertures are provided in plate 2 for connections from theradio-frequency unit to the control unit. Inasmuch as these aperturesare within housing 60 the wires may be directly connected to the controlunit without any special provision therefor in the housing. This chassisis completed by a bottom cover plate 68 suitably bolted to pan 1.

It will be noted that the control unit is parallel and adjacent theradio-frequency unit, thus making for short connections between saidunits.

While I have shown preferred embodiments of my invention it will beobvious that various modifications may be made without departing fromthe spirit and scope as defined by the appended claims.

What I claim is:

1. A radio chassis comprising three distinct bases, apparatus directlysecured to one base, radio frequency and control apparatus respectivelydirectly secured to each of the other two bases, one of said basescomprising a rectangular-1y shaped pan, said pan having largeindividually shielded elements on the outside thereof and wiringterminal boards and small elements on the inside thereof, and means forsecuring each of the other two bases on the inside and outside of saidpan respectively.

2. A radio chassis comprising three distinct bases, audio-frequency andantenna tuning apparatus directly secured to one base, radio frequencyand control apparatus respectively directly secured to each of the othertwo bases, one of said bases comprising a rectangularly" shaped pan,said pan having large individually shielded elements on the outsidethereof and wiring terminal boards and small elements on the insidethereof, and means for securing each of the other two bases on theinside and outside of said pan, respectively, and parallel to eachother.

3. A radio chassis comprising a supporting pan having substantiallyrectangular sides and a bottom and having an opening in the bottomthereof, said pan having large individually shielded elements on theoutside thereof and wiring terminal boards and small elements on theinside thereof, audiofrequency and antenna tuning apparatus directlysecured to said pan on the bottom, a base, radio frequency apparatusdirectly secured to saidbase, means for securing said base to said panover said opening and parallel to an edge of said pan, another base,control apparatus directly secured to said other base, and means forsecuring said other base to said pan, said two bases being secured onthe opposite sides of the pan wall and parallel to each other.

4. In a radio chassis, a radio frequency sub-assembly adapted to beinserted into or removed from said chassis as a unit, said subassemblycomprising a U-shaped mounting member provided with a plurality ofapertures and radio frequency apparatus, including a plurality ofvariable neutralizing condensers mounted thereon, said condensers beingon the inside of said mounting member and in registry with the aperturesthereof whereby said condensers may be adjusted from the outside of saidmember.

5. In a radio chassis, a radio frequency sub-assembly adapted to beinserted into or removed from said chassis as a unit, said subassemblycomprising a U-shaped mounting member provided with a plurality ofapertures, a plurality of vacuum tube sockets secured on said mountingmember, each of said sockets being disposed adjacent an aperture, radiofrequency apparatus including a plu rality of neutralizing condensersmounted on said member, means for varying the capacity of each of saidcondensers, said condensers being secured on the inside of said mountingmember, each condenser being disposed in such a manner that the capacityadjusting means is in registry with each aperture whereby the capacityof said condensers may be varied from the outside of said mountingmember.

6. In a radio chassis, a radio frequency sub-assembly adapted to beinserted into or removed from said chassis as a unit, said subassemblycomprising a U-shaped mounting member having a plurality of aperturestherethrough, radio frequency apparatus including a plurality ofneutralizing condensers mounted thereon, part of the radio frequencyapparatus being secured on the outside of said mounting member, the restof the apparatus including said condensers being secured on the insideof each mounting member, and means for varying the capacity of each ofsaid condensers, said means being disposed in registry with saidapertures.

7. A radio chassis comprising a pan shaped base having an opening in onewall, apparatus directly secured thereto, a second base, radio frequencyappa atus directly secured thereto, means for securing said second baseto said pan over the opening, all said radio frequency apparatus beingwithin the pan, a third base, control apparatus secured to said thirdbase, means for securing said third base to said pan adjacent theopening in said pan, said second and third bases being parallel, and ahousing for said control. apparatus secured to said pan and second base.

8. In a radio chassis, a pan shaped base provided with an opening in onewall thereof, apparatus directly secured thereto, a U- shaped base,radio frequency apparatus directly secured thereto, and means forsecuring said U-shaped base to the inside of said pan at said openingwhereby all radio frequency apparatus is substantially within the pan.

9; A radio chassis comprising a pan shaped base having an opening in thebottom thereof, audio-frequency and antenna tuning apparatus directlysecured thereto,

part of the apparatus being within the pan and part being on the outsideof the pan, said exterior apparatus including large individuallyshielded elements, a U-shaped base, radio frequency apparatus directlysecured 10 to said base, means for mounting said U- shaped base to theinside of said pan at the opening whereby substantially all radiofrequency apparatus is within the pan, another base, control apparatussecured to said other base, means for mounting said other base on theoutside of said pan, and a housing for said control apparatus secured tosaid pan and U-shaped member.

10. A radio chassis comprising a shallow '20 pan having a substantiallyrectangular bottom, and upstanding side walls, said bottom beingprovided with an elongated opening along one side thereof, a U-shapedbase, a plurality of vacuum tube sockets mounted '25 on the bightportion of said U so that vacuum tubes, when plugged into said sockets,may project outwardly therefrom, a plurality of radio-frequencytransformers mounted upon one of the arms of said U, said transformersbeing mounted in line so that they project outwardly from said U, meansfor mounting said U-shaped base on the bottom of said pan and over saidopening thereof so that the bight of the U covers said opening, and saidradio-frequency transformers project inwardly toward the center of saidpan, and means for mounting remaining elements of a radio receiving seton said pan H V and said U-shaped member.

11. The structure of claim 10 in which a gang condenseris mounted on thebottom wall of said pan adjacent said opening so that said gangcondenser is disposed on the ,7 other side of said pan bottom and inline with the radio-frequency transformers.

12. The structure of claim 10 in which a gang condenser is mounted onthe outside of the bottom of said pan adjacent said open- H ing, andaudio-frequency transformers are mounted on the outside of said panbottom on the side of said gang condenser remote from said openin Intestimony whereof he aiiixes his signa- MAHLON WV. KENNEY.

